textproduct: Quad Cities

KEY MESSAGES

- A storm system will drag a cool front through the area tonight into Wednesday, bringing some showers and thunderstorms. A couple of storms may be strong to severe but confidence is low.

- Outside of another front bring a shower and thunderstorm risk to the area late Thursday night into Friday evening, precipitation chances look to be very limited over the next 7 days.

SHORT TERM /THROUGH WEDNESDAY/

Issued at 147 PM CDT Tue Aug 18 2026

Satellite trends show clearing occurring ahead of the approaching cool front. The overall forcing is weak as is the convergence along the front. Thus there are questions regarding the potential for rain.

Based on radar/satellite trends through early afternoon, prudence dictates going with a 15-50 percent chance of rain late this afternoon with the better chances north of Highway 30.

The cloud cover and relatively cooler temperatures will result in limited instability for storms. However, progged soundings of the atmosphere do give weak support that a couple of storms could be strong to severe. IF this scenario does occur, the primary risk would be hail for areas along/north of Highway 30.

Once sunset occurs the overall coverage of convection will drop with some weak but isolated convection festering the remainder of the night.

On Wednesday there should be some lingering convection south of I-80 during the morning that slowly dissipates. If diurnal convection develops Wednesday afternoon, it would be isolated due to the lack of upper air support and would be confined to areas south of I-80.

LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/

Issued at 147 PM CDT Tue Aug 18 2026

Wednesday night through Tuesday... Assessment...low (20-30%) confidence on late week rain chances

The models have another front moving through the area in the late Thursday night through Friday evening time frame. Northwest flow aloft dominates well into next week so the overall moisture available for rain will be limited. The current model consensus is at a 20-35% chance of rain with the better chances generally along and north of I-80.

Outside of this time period, the prospects for rain is very limited with temperatures near normal.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 1221 PM CDT Tue Aug 18 2026

Weak forcing ahead and along an approaching cold front should generate isolated (20-30%) coverage of SHRA/TSRA through 06z/19 across eastern Iowa and northern Illinois. After 06z/19 light winds should result in pockets of MVFR/IFR conditions in light fog. Fog that forms should burn off by 15z/19.

DVN WATCHES/WARNINGS/ADVISORIES

IA...None. IL...None. MO...None.